Shrouded electrical connectors are well known in the connector industry. The connectors include at least two, and typically at least three, prongs extending from a housing for joining with a complementary number of holes in a female connector. The male connectors usually include a cylindrical shroud extending from the base and encircling the prongs. The shroud is normally at least as long as the prongs and is often slightly longer than the prongs such that the prongs are slightly recessed in the shroud. The shroud primarily serves to protect the prongs from damage during shipping and handling of the connector. The mating female receptacle may be a cylindrical shape to be received within the shroud or may have a cylindrical recess encircling the prong-receiving holes to receive the shroud.
Electrical conductor assemblies of the locking type to prevent inadvertent connection are also known in the connector industry. The electrical connectors usually include a lock mechanism which encloses the male prongs of the connector or otherwise provides an obstruction to prevent the electrical conductor from being coupled with a female connector. The male and female portions can take various configurations, but the male portion is usually a plug connected to the end of a multi-connector cable. The female portion may also be connected to a similar cable. Alternatively, the female connector may be a fixture or receptacle mounted on a support or a piece of equipment. The male portion is subject to inadvertent connection to a power source which can result in undesirable operation of electrical equipment or electrical shock to an operator and the injuries associated therewith.
Recent regulations enacted by the Occupational Safety and Health Administration (OSHA) require safety mechanisms to prevent the inadvertent and unauthorized connection of electrical conductors. These regulations require a locking mechanism such that the electrical connector cannot be inadvertently connected to a power source while an electrical device is being serviced or otherwise in a condition where the power is undesired. The locking mechanisms must provide limited access and require a key or other security device to prevent unauthorized connection.
Efforts have been made in the past to produce a locking connector and particularly locking male connectors to prevent unauthorized connection. Examples of various locking connectors may be found in U.S. Pat. No. 4,241,969 to D'Amato; U.S. Pat. No. 5,046,961 to Hoffman; U.S. Pat. No. 2,844,805 to Darrell, and U.S. Pat. No. 3,790,914 to Hough.
The above-noted patents disclose locking mechanisms which are relatively complex and expensive to produce. In addition, some of these locking mechanisms are complicated to manufacture and use and require a large number of moving parts which are subject to failure. Furthermore, some of the previous locking mechanisms have not provided the necessary security to prevent unauthorized use of the connector.